Providing such forward access has become an important aspect for high availability systems. Where a component such as a card or power supply fails or deteriorates to evoke a warning status, it is important that service personnel be capable of replacing it promptly. Being able to carry out that prompt servicing calls for front access to the components mounted in the mainframe. To further facilitate such rapid and relativity straight-forward component exchange, standards organizations are commencing to specify a feature wherein components are plugged into the system from the forward location while it is actively running. This feature is referred to as xe2x80x9chot swappingxe2x80x9d. One approach to providing power supplies which are accessible from the front of the mainframe is described in U.S. Pat. No. 5,940,288, issued Aug. 17, 1999 by Kociecki, entitled xe2x80x9cCard Cage Mounted Power Supply With Heat Dissipating Architecturexe2x80x9d. The power supply described therein is thin, having a standard slot height and is inserted within a card slot in the same manner as a card. Heat removing airflow is provided to the power supply by the cooling fans which also are utilized to remove heat from the array of cards. Because the power supplies are connected into the backplane by a conventional pin array the necessity for bolted cable connections utilizing rather robust studs is eliminated and the capability for carrying out hot swapping is achieved.
As the systems at hand have become more complex, however, a concomitant requirement for additional card slot space has arisen. Thus, a need is present for a modular form of power supply which is forwardly accessible and exhibits a small size or form factor permitting it to be mounted adjacent the card cage without interfering with that function. This calls for not only diminutive volumetric sizes of the power supply but correspondingly small and preferably multitask handling structures.
Over the recent past, multiple output power supplies with mutually independent outputs have been introduced which achieve a somewhat reduced package size through the utilization of pre-manufactured switching converters, permitting improved power packaging densities. Manufacturers offer them as xe2x80x9cbricksxe2x80x9d, the converters generally being rectangularly shaped packages of typically flat configuration (i.e., one-half inch thickness), one side of which incorporates a heat transfer surface generally formed of aluminum. With the introduction of the switching converters, improved packaging and cooling techniques have been developed. See in this regard: Tracewell, et al, application for U.S. Pat. No. 5,945,746, entitled xe2x80x9cPower Supply and Power Supply/Backplane Assembly and Systemxe2x80x9d, issued Aug. 31, 1999; Tracewell, et al, U.S. Pat. No. 6,046,921 entitled xe2x80x9cModular Power Supplyxe2x80x9d, issued Apr. 4, 2000; and U.S. Pat. No. 5,940,288 (supra).